Monday, February 4, 2013

Our clouds are full of bacteria

Researchers from the Georgia Institute of Technology and
NASA have been sampling the air in the upper troposphere (extending up to between 7 and 20 km, depending on the location and
time of year). And what did they find? Lots and lots of bacteria.

We knew that clouds weren’t composed solely of water
molecules. For one thing, storms often kick dust and debris up into the sky. As
I’ve previously written, these particles can traverse the world before raining
back down on Earth. For another, the very formation of clouds sometimes
requires nucleation centers to start the water molecules freezing. Inorganic
dust works well for this purpose, but some types of bacteria might be even
better. After all, some plant pathogens work by serving as nucleation centers in
leaves; the resultant freeze of the plant tissues damages them enough to allow
the bacteria to enter.

The scientists took the air samples at various altitudes
around the country both during and after hurricanes. I don’t envy the person
whose job it was to fly an airplane through a hurricane and collect a
cup of air. In any case, the scientists found that about 20% of
the microscopic particulates were in fact bacterial cells. Even more intriguingly, most of the bacteria even at the highest elevations were alive.

Not surprisingly, hurricanes tend to alter the composition
of the microbial communities quite a bit. It was only during hurricanes that
bacteria associated with human or animal feces appeared in the samples, as good
a reason as any not to go outside during a hurricane.

Stochastic Scientist? What's up with that?

Why the Stochastic Scientist? As I'm sure you all know, 'stochastic' is another word for 'random', which is what I intend for the focus of this blog. Although my formal training is as a molecular biologist, there are many other fields of science that are also fascinating and beautiful. It's my intention to blog about which ever scientific discovery or invention catches my, and hopefully your, fancy.

I also hope to inspire people to learn more about science. By choosing among a huge variety of scientific endeavors, I'll undoubtably hit upon something that will pique my readers' interest.

I guess I could have called my blog 'The Joy of Science', but that wouldn't have been quite so random.